Rashi in the beginning of Vayikra Perek 11 quotes the Midrash Tanchuma about why we were commanded kashrus:

A doctor has two patients, one of whom has hope of being cured and one who does not. To the one who does not, the doctor allows him to eat whatever he wants, because it doesn't make a difference. To the one who does, however, the doctor restricts what he can eat so that he will recover.

Jews have a hope of developing a relationship with HKBH, so what we eat makes a difference, and we were thus commanded; non-Jews don't share such benefits.

If so, we can apply this idea to the rest of the Torah--specifically zera levatala:

Every Jew has a hope of being cured. As long as you're Jewish, you're commanded, because there is yet hope that you will develop a relationship with Hashem and keep his Torah.

If you're Jewish, you still haven't lost hope.